Progression to B acute lymphoblastic leukemia in 8p11 myeloproliferative syndrome with t(6;8)(q27;p12).

8p11 myeloproliferative syndrome is a rare hematological malignancy caused by the translocation of FGFR1. Patients present with a myeloproliferative neoplasm that frequently transforms into acute myeloid leukemia or T-lymphoblastic lymphoma/leukemia. Here, we report a molecular study of a patient with 8p11 myeloproliferative syndrome who developed acute B-lymphoblastic leukemia and then transformed to mixed-phenotype acute leukemia. A 67-year-old woman was diagnosed with a myeloproliferative neoplasm with t(6;8)(q27;p12) and was monitored for polycythemia vera. Four years later, she developed acute B-lymphoblastic leukemia with an additional chromosomal abnormality of - 7. Despite two induction regimens, she failed to achieve complete remission, and leukemia transformed into mixed-phenotype leukemia. Targeted sequencing of serial bone marrow samples identified the RUNX1 L144R mutation upon transformation to B-cell leukemia. After those two induction regimens, some RUNX1 mutation-positive leukemic cells obtained the JAK2 V617F mutation, which was associated with the emergence of myeloid markers, including myeloperoxidase.

Emergence of t(3;21)(q26.2;q22) during eltrombopag treatment in a patient with relapsed aplastic anemia who received chemotherapy for angioimmunoblastic T-cell lymphoma.

A 65-year-old man with nonsevere aplastic anemia received rabbit anti-thymocyte globulin and cyclosporine and partially responded. Six months after the initiation of treatment, he was diagnosed with stage IV angioimmunoblastic T-cell lymphoma and received chemotherapy. PET/CT scan analysis indicated a complete response. However, he showed sustained myelosuppression and was diagnosed with relapse of aplastic anemia. He did not respond to cyclosporine, eltrombopag or methenolone. Fifteen months after eltrombopag administration, he developed MDS with t(3;21)(q26.2;q22). Patients should be monitored carefully for the emergence of not only -7/del(7q) but also 3q26 abnormalities, including t(3;21)(q26.2;q22), during and after eltrombopag treatment.

Essential thrombocythaemia with aggressive megakaryocytosis after myelofibrotic transformation.

BACKGROUND: Among myeloproliferative neoplasms, it is often difficult to distinguish essential thrombocythaemia (ET) from prefibrotic-stage primary myelofibrosis (PMF) with thrombocytosis given their overlapping clinicopathological phenotypes. CASE PRESENTATION: We encountered a 45-year-old male who was initially diagnosed with ET and eventually became transformed to secondary myelofibrosis 20 years later. Two distinct types of aberrant megakaryocytes were observed at diagnosis: one type characteristic of ET and the other type characteristic of PMF. With a proliferation in the bone marrow, aberrant megakaryocytes were infiltrated into the extramedullary organs and were even present in the thrombus were observed at autopsy. As a result of next-generation sequencing, the significant increase of variant allele frequency (VAF) of JAK2 V617F and U2AF1 S34Y mutations was observed in the bone marrow cells at the final stage. CONCLUSIONS: This patient could be recognized as an atypical case of aggressive megakaryocytosis transformed from ET.

Clonal evolution and clinical implications of genetic abnormalities in blastic transformation of chronic myeloid leukaemia.

Blast crisis (BC) predicts dismal outcomes in patients with chronic myeloid leukaemia (CML). Although additional genetic alterations play a central role in BC, the landscape and prognostic impact of these alterations remain elusive. Here, we comprehensively investigate genetic abnormalities in 136 BC and 148 chronic phase (CP) samples obtained from 216 CML patients using exome and targeted sequencing. One or more genetic abnormalities are found in 126 (92.6%) out of the 136 BC patients, including the RUNX1-ETS2 fusion and NBEAL2 mutations. The number of genetic alterations increase during the transition from CP to BC, which is markedly suppressed by tyrosine kinase inhibitors (TKIs). The lineage of the BC and prior use of TKIs correlate with distinct molecular profiles. Notably, genetic alterations, rather than clinical variables, contribute to a better prediction of BC prognosis. In conclusion, genetic abnormalities can help predict clinical outcomes and can guide clinical decisions in CML.

Development of Philadelphia chromosome-negative acute myeloid leukemia with IDH2 and NPM1 mutations in a patient with chronic myeloid leukemia who showed a major molecular response to tyrosine kinase inhibitor therapy.

Tyrosine kinase inhibitors (TKIs) are standard therapies for chronic myeloid leukemia (CML) that can eradicate Ph-positive leukemic cells. However, disease control is not achievable in a minority of cases, most commonly due to evolution of TKI-resistant clones. There have also been rare cases of emergence of Ph-negative clones with other cytogenetic abnormalities, and, less commonly, development of Ph-negative acute myeloid leukemia (AML), whose molecular pathogenesis is largely unknown. Here we report molecular features of a patient with Ph + CML who developed Ph-negative AML after showing a major molecular response to dasatinib. A 55-year-old man was diagnosed with CML. He achieved a complete cytogenetic response three months after dasatinib therapy but developed AML with normal karyotype 1 year later. After receiving induction and consolidation chemotherapy for AML, the patient achieved complete remission with no evidence of CML under maintenance with bosutinib. Targeted sequencing of serial bone marrow samples identified mutations in IDH2 and NPM1 in the Ph-negative AML cells, which had not been detected in CML cells. These results suggest that Ph-negative AML in this patient originated from a preleukemic population, which might have expanded during or after the successful elimination of CML clones with TKI therapy.

Clinical implications of 18F-sodium fluoride uptake in subclinical aortic valve calcification: Its relation to coronary atherosclerosis and its predictive value.

BACKGROUND: Uptake of 18F-sodium fluoride (18F-NaF) on positron emission tomography (PET) reflects active calcification. Application of this technique in the early phase of aortic valve calcification (AVC) is of clinical interest. We investigated clinical implications of 18F-NaF uptake in subclinical AVC evaluated simultaneously with coronary atherosclerosis, and the utility of 18F-NaF uptake in predicting AVC progression. METHODS: We studied 25 patients with subclinical AVC and coronary plaques detected on computed tomography (CT) who underwent 18F-NaF PET/CT. AVC score, volume, mean density, and the presence of high-risk coronary plaque were evaluated on CT in each patient. Focal 18F-NaF uptake in AVC and in coronary plaques was quantified with the maximum tissue-to-background ratio (TBRmax). RESULTS: There were positive correlations between AVC TBRmax (A-TBRmax) and AVC parameters on CT. The 14 patients with high-risk coronary plaque had significantly higher A-TBRmax than those without such plaque (1.60 ± 0.18 vs 1.42 ± 0.13, respectively; P = 0.012). A-TBRmax positively correlated with maximum TBRmax of coronary plaque per patient (r = 0.55, P = 0.0043). In the 11 patients who underwent follow-up CT scan, A-TBRmax positively correlated with subsequent increase in AVC score (r = 0.74, P = 0.0091). CONCLUSION: Our 18F-NaF PET- and CT-based data indicate relationships between calcification activity in subclinical AVC and characteristics of coronary atherosclerosis. 18F-NaF PET may provide new information regarding molecular conditions and future progression of subclinical AVC.

Efficacy and safety of romiplostim in refractory aplastic anaemia: a Phase II/III, multicentre, open-label study.

A previous dose-finding study has suggested that romiplostim is effective in patients with refractory aplastic anaemia (AA) and 10 µg/kg once weekly was recommended as a starting dose. In this Phase II/III, multicentre, open-label study, romiplostim was administered subcutaneously at a fixed dose of 10 µg/kg once weekly for 4 weeks (weeks 1-4) followed by weekly doses (5, 10, 15 and 20 µg/kg) titrated by platelet response for up to 52 weeks (weeks 5-52). A total of 31 patients with AA who were refractory to immunosuppressive therapy (IST) and thrombocytopenia (platelet count of ≤30 × 109 /l) were enrolled. The primary efficacy endpoint of the proportion of patients achieving any haematological (platelet, neutrophil and erythrocyte) response at week 27 was 84% [95% confidence interval (CI) 66-95%]. Trilineage response was 39% (95% CI 22-58%) at week 53. The most common treatment-related adverse events (AEs) were headache and muscle spasms (each 13%). All AEs were mild or moderate except for three patients with Grade 3 hepatic AEs; no AEs necessitated romiplostim discontinuation. Two patients developed cytogenetic abnormalities, of whom one returned to normal karyotype at last follow-up. High-dose romiplostim is effective and well tolerated in the treatment of patients with AA refractory to IST.

The lysophospholipase D enzyme Gdpd3 is required to maintain chronic myelogenous leukaemia stem cells.

Although advanced lipidomics technology facilitates quantitation of intracellular lipid components, little is known about the regulation of lipid metabolism in cancer cells. Here, we show that disruption of the Gdpd3 gene encoding a lysophospholipase D enzyme significantly decreased self-renewal capacity in murine chronic myelogenous leukaemia (CML) stem cells in vivo. Sophisticated lipidomics analyses revealed that Gdpd3 deficiency reduced levels of certain lysophosphatidic acids (LPAs) and lipid mediators in CML cells. Loss of Gdpd3 also activated AKT/mTORC1 signalling and cell cycle progression while suppressing Foxo3a/ß-catenin interaction within CML stem cell nuclei. Strikingly, CML stem cells carrying a hypomorphic mutation of Lgr4/Gpr48, which encodes a leucine-rich repeat (LRR)-containing G-protein coupled receptor (GPCR) acting downstream of Gdpd3, displayed inadequate disease-initiating capacity in vivo. Our data showing that lysophospholipid metabolism is required for CML stem cell maintenance in vivo establish a new, biologically significant mechanism of cancer recurrence that is independent of oncogene addiction.

[Effective treatment of POEMS syndrome accompanied by plasmacytoma with lenalidomide, dexamethasone, and local irradiation].

A 70-year-old woman experienced pain in both gastrocnemius muscles, numbness in the toes, and muscle weakness in both the legs that lasted for two months. After getting admitted to our hospital, the muscle weakness extended to both her arms, and nerve conduction studies revealed decreased nerve conduction velocity, which was more prominent in the elbow and the axilla than in the wrist. A magnetic resonance imaging revealed a tumor in the right femoral neck, which was histologically diagnosed as plasmacytoma. Laboratory findings revealed IgA lambda type M protein and an elevated VEGF level of 2,320 pg/ml; edema was present in both the legs. After a diagnosis of POEMS syndrome, lenalidomide and dexamethasone treatment were initiated simultaneously, along with irradiation. The treatment improved polyneuropathy, along with a decrease in the VEGF level. Increased vascular permeability due to elevated VEGF led to the development of neuropathy of POEMS syndrome, and treatment against proliferating monoclonal plasma cells is effective. In the present case, we believe that a prompt control of the plasmacytoma with novel therapeutic agents for myeloma with irradiation resulted in the improvement of the neurological symptoms.

RUNX1-EVI1 induces dysplastic hematopoiesis and acute leukemia of the megakaryocytic lineage in mice.

The RUNX1-EVI1 gene generated by the t(3;21) translocation encodes a chimeric transcription factor and is a causative gene in the development of de novo acute megakaryoblastic leukemia and leukemic transformation of hematopoietic stem cell tumors. Heterozygous RUNX1-EVI1 knock-in mice die in utero due to hemorrhage in the central nervous system and spinal cord and complete abolishment of definitive hematopoiesis in the fetal liver. On the other hand, the chimeric knock-in mouse develops acute megakaryoblastic leukemia. We created another mouse model of RUNX1-EVI1 using transplantation of retrovirus-infected bone marrow cells. Some mice transplanted with RUNX1-EVI1-expressing bone marrow cells developed acute megakaryoblastic leukemia within eight months, and the other non-leukemic mice showed thrombocytosis at around a year. In the non-leukemic mice, dysplastic megakaryocytes proliferated in the bone marrow and frequently infiltrated into the spleen, which was not associated with marrow fibrosis. In the leukemic mice, their tumor cells were positive for c-kit and CD41, and negative for TER119. Although they were negative for platelet peroxidase in the electron microscopic analysis, they had multiple centrioles in the cytoplasm, which are characteristic of megakaryocytes that undergo endomitosis. The leukemic cells were serially transplantable, and gene-expression analyses using quantitative RT-PCR arrays revealed that they showed significantly elevated expression of stem cell, primitive hematopoietic cell and endothelial cell-related genes compared with normal bone marrow cells. All these data suggested that RUNX1-EVI1 caused dysplastic hematopoiesis or leukemia of the megakaryocytic lineage and endowed gene expression profiles distinctive of immature hematopoietic cells.

[Systemic organ invasion accompanied by immunophenotypic change observed in extraosseous plasmacytoma].

We report a 57-year-old man who was diagnosed based on morphological findings as having extraosseous plasmacytoma of the left lower eyelid. Tumor cells were positive not only for CD38 and CD138, but also for CD19 and surface immunoglobulin lambda chain. He obtained a complete remission with irradiation and VAD therapy, but the disease relapsed one year later in the testis and popliteal fossa. Because tumor cells appeared to be blastoid, CHOP therapy was administered, and the patient achieved a temporary remission. Cytoplasmic lambda chain-positive and CD19-negative tumors eventually recurred at multiple sites including the central nervous system but not in the bone marrow. Treatment with the BD regimen and lenalidomide failed, and he died four years after the initial diagnosis.

Chronic myelogenous leukemia in chronic phase transforming into acute leukemia under treatment with dasatinib 4 months after diagnosis.

We report a 64-year-old woman morphologically diagnosed with chronic myelogenous leukemia in the chronic phase. Despite having achieved a complete hematological response following treatment with dasatinib, she developed lymphoblastic crisis 4 months later. Blastic cells were in a CD45-negative and SSC-low fraction, and positive for CD10, CD19, CD34, and HLA-DR expression and rearrangement in the immunoglobulin heavy chain gene. Chemotherapy using the HyperCVAD/MA regimen led to a complete cytogenetic response, and after cord blood transplantation, she obtained a complete molecular remission. However, the crisis recurred 6 months later. Another salvage therapy using L-AdVP regimen followed by nilotinib led to a complete molecular remission. Retrospective analyses using flow cytometry and polymerase chain reaction revealed a minimal blastic crisis clone present in the initial marrow in chronic phase. This case is informative as it suggests that sudden blastic crisis may occur from an undetectable blastic clone present at initial diagnosis and that leukemic stem cells may survive cytotoxic chemotherapy that eliminates most of the blastic cells.

Expressional changes of genes and miRNA in common megakaryocyte-erythroid progenitors from lower-risk myelodysplastic syndrome.

Myelodysplastic syndrome (MDS) is a stem cell tumor characterized by dysplastic features and ineffective hematopoiesis in the early phase and leukemic progression in the late phase. Speculating that differences in the expression of genes and microRNA (miRNA) in control and MDS-derived erythroid progenitors may cause ineffective erythropoiesis, we sorted common megakaryocyte-erythroid progenitors (MEPs) in bone marrow cells from three lower-risk MDS patients, and compared expression levels of genes and miRNA with those from controls. In apoptosis-related pathways, the expression of some pro-apoptotic genes, such as cell death-inducing DFFA-like effector A, caspase 5, and Fas ligand, was elevated in MDS-derived MEPs, while those of anti-apoptotic CD40 and tumor necrosis factor were lower. In hematopoiesis-regulating pathways, RUNX1 and ETV6 genes showed reduced expression. Expression profiling revealed that three and 35 miRNAs were significantly up- and down-regulated in MDS-derived MEPs. MIR9 exhibited robust expression in MEPs and CD71+GlyA+ erythroid cells derived from one of the three patients. Interestingly, overexpression of MIR9 inhibited the accumulation of hemoglobin in UT-7/GM cells. Some of these alterations in gene and miRNA expression may contribute to the pathogenesis of ineffective hematopoiesis in lower-risk MDS and provide molecular markers for sub-classification and making a prognosis.

Overexpression of MIR9 indicates poor prognosis in acute lymphoblastic leukemia.

Aberrant expression of MIR9 predicts a poor prognosis in acute myelogenous leukemia. To evaluate its clinical significance in acute lymphoblastic leukemia, we analyzed expression levels of MIR9 in bone marrow samples from patients with acute lymphoblastic leukemia and compared them to those in normal bone marrow cells. Approximately 20% of them showed higher expression compared with controls. There was a tendency that patients who showed overexpression of MIR9 underwent worse clinical courses, but without statistical significance. However, when the analyses were restricted to patients who did not receive a stem cell transplant, overexpression of MIR9 was significantly associated with worse overall survival. Interestingly, exaggerated MIR9 expression and higher white blood cell count at presentation were independent unfavorable prognostic factors in all patients for overall survival by multivariate analysis. The presence of higher MIR9 expression could be a useful indicator for treatment stratification.

Prednisone versus high-dose dexamethasone for untreated primary immune thrombocytopenia. A retrospective study of the Japan Hematology & Oncology Clinical Study Group.

High-dose dexamethasone (HDD) has been shown to be an effective initial treatment for immune thrombocytopenia (ITP), but it is not clear whether HDD offers any advantages over conventional-dose prednisone (PSL). We retrospectively compared the efficacy and toxicity of HDD and PSL for newly diagnosed ITP. The response was evaluated according to the International Working Group (IWG) criteria. We analyzed data from 31 and 69 patients in the HDD and PSL groups, respectively. There were no significant differences in patient characteristics between the two groups except for the incidence of the eradication of Helicobacter pylori. The response rate was better in the HDD group (42.7 vs. 28.4 %), and this difference was statistically significant when adjusted for other factors including the eradication of H. pylori. In the HDD group, a response was achieved earlier (28 vs. 152 days in median) and steroids were more frequently discontinued at 6 months (64.5 vs. 37.7 %). Among patients who achieved a response, there was no significant difference in the incidence of loss of response. There were no significant differences in the rate of adverse events, transition to chronic ITP, and splenectomy. In conclusion, HDD might enable the early cessation of steroids without a loss of response.

[Detection of BCR-ABL1 chimeric gene-positive neutrophils in a patient with mixed phenotype acute leukemia].

We experienced two patients with mixed phenotype acute leukemia with t(9;22)(q34;q11.2); BCR-ABL1 according to the WHO classification 2008. The type of BCR/ABL1 was major in both patients, and the chimeric gene was also detected in neutrophils from peripheral blood by the fluorescence in situ hybridization technique. Patient 1 was a 59-year-old Japanese woman, and patient 2 a 45-year-old Japanese man. They had both developed leukemia suddenly. Their leukemic blasts expressed B cell and myeloid cell antigens, but concomitantly in patient 1 (biphenotypic) and separately in patient 2 (biclonal). Percentages of BCR-ABL1-positive neutrophils were 98% and 89%, respectively. Both patients received an imatinib (600 mg/day)-combined Hyper-CVAD regimen as induction therapy, followed by treatment with dasatinib (140 mg/day). MEC therapy was also applied between these two treatments in patient 2. At present, patient 1 has obtained complete molecular remission quantitatively and qualitatively, and patient 2 only quantitatively. Considering their acute onsets with no prior history of chronic myelocytic leukemia (CML), they were both diagnosed as having acute leukemia with Ph1, but not blastic crisis of CML. In this tyrosine kinase inhibitor era, it has become more difficult to differentiate these two types of Ph1-positive leukemia development.

[Inv(16)-type acute myeloid leukemia with repeated skin infiltration without bone marrow relapse before and after allogeneic hematopoietic stem cell transplantation].

We report a 40-year-old woman diagnosed as having acute myeloid leukemia with CBFB-MYH11. Before and after stem cell transplantation in the phase of molecular remission of the marrow, CBFB-MYH11-positive cells were detected by RT-PCR analysis in skin lesions. The former was pathologically diagnosed as leukemic infiltration, while the latter was considered to be graft-versus-host disease. We can speculate that a low level of leukemic stem cells not detectable by RT-PCR analysis remained in the bone marrow, at least prior to transplantation. This case may suggest interesting biological features of inv(16)-type acute myeloid leukemia.